Cheapest priced copy (The Lost Caverns of Ixalan Commander): $0.99 at Card Kingdom, near mint, their price list as of .
Admiral Brass, Unsinkable 
Legendary Creature — Human Pirate · 3/3 · Mythic · The Lost Caverns of Ixalan Commander · #17
When Admiral Brass enters, mill four cards.
At the beginning of combat on your turn, you may return target Pirate creature card from your graveyard to the battlefield with a finality counter on it. It has base power and toughness 4/4. It gains haste until end of turn. (If a creature with a finality counter on it would die, exile it instead.)
Legal inCommanderLegacyVintage
Not legal inBrawlStandardPioneerModernPauper
4 printings · $0.99 to $2.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| The Lost Caverns of Ixalan Commander | 1 | Mythic | $0.99 | $0.99 |
| The Lost Caverns of Ixalan Commander | 17 | Mythic | $0.99 | $2.49 |
| The Lost Caverns of Ixalan Commander | 25 | Mythic | $0.99 | $1.49 |
| The Lost Caverns of Ixalan Commander | 121 | Mythic | — | — |
5 rulings from Wizards of the Coast
- 10 November 2023Finality counters don't stop permanents from going to zones other than the graveyard from the battlefield. For example, if a permanent with a finality counter on it would be put into its owner's hand from the battlefield, it does so normally.
- 10 November 2023Finality counters work on any permanent, not only creatures. If a permanent with a finality counter on it would be put into a graveyard from the battlefield, exile it instead.
- 10 November 2023Finality counters aren't keyword counters, and a finality counter doesn't give any abilities to the permanent it's on. If that permanent loses its abilities and then would go to a graveyard, it will still be exiled instead.
- 10 November 2023Multiple finality counters on a single permanent are redundant.
- 10 November 2023Admiral Brass, Unsinkable's effect will overwrite any previous effects that set the returned creature's power and toughness to specific numbers. Effects that otherwise modify the returned creature's power and toughness will still apply no matter when they took effect. The same is true for +1/+1 counters.